Abnormal sound diagnosis program

Abstract

To provide an abnormal sound diagnosis program capable of accurately diagnosing that abnormal sound of a vehicle is caused by opening of an oil tank to the atmosphere at stopping of an engine.SOLUTION: An abnormal sound diagnosis program of the present invention is a program for diagnosing abnormal sound of a vehicle which includes oil piping through which blow-by gas flows from an engine to an oil tank, blow-by gas piping through which the blow-by gas flows from the oil tank to an intake pipe of the engine, a check valve which is provided in the blow-by gas piping so as to allow flowing of the blow-by gas from the oil tank to the intake pipe and to restrict flowing of the blow-by gas in the opposite direction, and an atmosphere open valve which opens the oil tank to the atmosphere when pressure in the oil tank at stopping of the engine is negative. Determination processing is executed for determining whether abnormal sound generated when the pressure in the oil tank is negative and the engine is stopped is eliminated by not opening the atmosphere open valve, and it is diagnosed that the abnormal sound is caused by opening of the atmosphere open valve at stopping of the engine when affirmative determination is made by the determination processing.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to an abnormal sound diagnosis program. [Background technology]

[0002] When the engine stops due to negative pressure in the oil tank, there is a technique for eliminating the negative pressure by introducing gas into the oil tank (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2018-044448 Summary of the Invention [Problem to be solved by the invention]

[0004] One method of introducing gas into an oil tank is to open the oil tank to the atmosphere. In a vehicle equipped with an engine, opening the oil tank to the atmosphere when the engine is stopped can introduce air into the oil tank, causing abnormal noise. For example, it is difficult for someone with no knowledge of abnormal vehicle noises to identify the cause of such abnormal noises.

[0005] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide an abnormal noise diagnosis program that can accurately diagnose that the cause of an abnormal noise from a vehicle is the oil tank being released to the atmosphere when the engine is stopped. [Means for solving the problem]

[0006] The above object can be achieved by an abnormal noise diagnosis program for diagnosing abnormal noise in a vehicle including an engine, an oil tank storing oil for lubricating the engine, an oil piping through which the oil flows from the oil tank to the engine and through which blow-by gas flows from the engine to the oil tank, a blow-by gas piping through which the blow-by gas flows from the oil tank to an intake pipe of the engine, a check valve provided in the blow-by gas piping that allows the flow of the blow-by gas from the oil tank to the intake pipe but restricts the flow of the blow-by gas in the opposite direction, and an air release valve that opens the inside of the oil tank to the atmosphere when the pressure in the oil tank becomes negative when the engine is stopped, the abnormal noise diagnosis program causing a computer to execute a determination process that determines whether abnormal noise generated when the engine is stopped due to the pressure in the oil tank being negative has been eliminated because the air release valve did not open, and a diagnostic process that diagnoses that the cause of the abnormal noise is the opening of the air release valve when the engine is stopped, if a positive determination is made by the determination process. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide an abnormal noise diagnosis program that can accurately diagnose that the cause of an abnormal noise from a vehicle is the oil tank being released to the atmosphere when the engine is stopped. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic diagram illustrating the configuration of an abnormal sound diagnosis system. [Figure 2] FIG. 1 is a schematic configuration diagram of an engine system. [Figure 3] 4 is a flowchart showing an example of an abnormal sound diagnosis process. DETAILED DESCRIPTION OF THE INVENTION

[0009] [Outline of abnormal noise diagnosis system] FIG. 1 is a schematic diagram of an abnormal sound diagnosis system 100. The abnormal sound diagnosis system 100 includes a vehicle A and a diagnosis terminal 40. An engine system B is mounted on the vehicle A. The engine system B, which will be described in detail later, includes an engine 1, an ECU (Electronic Control Unit) 20, and a dongle 21. The ECU 20 is a computer that includes a CPU (Central Processing Unit) and a storage device. The ECU 20 controls the operation of the engine 1.

[0010] The dongle 21 is configured as a communication device equipped with a wireless communication module. The dongle 21 is attached to a connection terminal provided, for example, below the steering wheel. This connection terminal is connected to the ECU 20. The dongle 21 wirelessly transmits information about the vehicle A from the ECU 20 to the diagnosis terminal 40.

[0011] The diagnostic terminal 40 is configured as a portable terminal that can be carried by staff at a vehicle dealership or workers at a repair shop. The diagnostic terminal 40 is, for example, a smartphone or tablet terminal, which is an example of a computer. The diagnostic terminal 40 includes a CPU 42, a storage device 44, a display 46, a touch panel 48, a speaker 50, a microphone 52, and a camera 54. These components are capable of communicating with each other via a communication line 58. The storage device 44 is an electrically rewritable non-volatile memory. The storage device 44 stores an abnormal sound diagnosis program 44a. The abnormal sound diagnosis program 44a is a program that causes the diagnostic terminal 40 to function as a device that diagnoses abnormal sounds in vehicle A. The CPU 42 executes a determination process and a diagnosis process, which will be described in detail later, in accordance with the abnormal sound diagnosis program 44a. The display 46 is, for example, configured with an LCD, an LED, or the like. The touch panel 48 is disposed on top of the display 46.

[0012] [Engine system overview] FIG. 2 is a schematic diagram of engine system B. Engine 1 includes a pair of banks 2L and 2R and a cylinder block 3. That is, engine 1 is a so-called V-type engine, but it may also be an in-line engine. Furthermore, engine 1 is a gasoline engine, but it may also be a diesel engine. A crankshaft 3a is rotatably mounted in cylinder block 3.

[0013] Banks 2L and 2R each have a plurality of cylinders. Intake pipes 4L and 4R are connected to banks 2L and 2R, respectively. From upstream to downstream, intake pipes 4L and 4R are provided with compressors 5L and 5R, throttle valves 6L and 6R, and surge tanks 7L and 7R, respectively. An exhaust passage is connected to banks 2L and 2R, respectively.

[0014] A pressure sensor 22 is connected to the ECU 20. The pressure sensor 22 detects the pressure in the space in the oil tank 10 that is filled with gas.

[0015] The oil tank 10 is a dry sump tank that stores oil for lubricating the engine 1. The oil tank 10 is connected to the cylinder block 3 of the engine 1 via an oil pipe 10a. When the scavenging pump P is driven, the oil used by the engine 1 flows into the oil tank 10 via the oil pipe 10a. Blow-by gas generated within the engine 1 also flows into the oil tank 10 via the oil pipe 10a. The scavenging pump P is a mechanical oil pump that is driven in conjunction with the rotation of the crankshaft 3a of the engine 1. The oil stored in the oil tank 10 is pressure-fed to the lubrication parts of the engine 1 by a feed pump (not shown).

[0016] An oil separator 11 is provided on top of the oil tank 10. The oil separator 11 separates oil from the blow-by gas introduced into the oil tank 10. The oil separated from the blow-by gas is stored in the oil tank 10. The oil separator 11 is provided with two check valves 12L and 12R. A blow-by gas pipe 13L connects the oil separator 11 to bank 2L via the check valve 12L. A blow-by gas pipe 13R connects the oil separator 11 to bank 2R via the check valve 12R. The check valve 12L allows gas to flow from the oil separator 11 to bank 2L but restricts gas to flow from bank 2L to the oil separator 11. The check valve 12R allows gas to flow from the oil separator 11 to bank 2R but restricts gas to flow from bank 2R to the oil separator 11.

[0017] Furthermore, blow-by gas pipes 15L and 15R are connected to the oil separator 11. The blow-by gas pipes 15L and 15R are connected to surge tanks 7L and 7R, respectively. Check valves 14L and 14R are provided on the blow-by gas pipes 15L and 15R, respectively. The check valve 14L allows gas to flow from the oil separator 11 to the surge tank 7L, but restricts gas from flowing from the surge tank 7L to the oil separator 11. The check valve 14R allows gas to flow from the oil separator 11 to the surge tank 7R, but restricts gas from flowing from the surge tank 7R to the oil separator 11.

[0018] The atmosphere release pipe 17 is connected to the oil separator 11 side of the check valve 14R of the blow-by gas pipe 15R and to the intake pipe 4R on the upstream side of the compressor 5R. An atmosphere release valve 18 is provided on the atmosphere release pipe 17. The atmosphere release valve 18 is electromagnetic and controlled by the ECU 20. The atmosphere release valve 18 is a normally closed type that closes the atmosphere release pipe 17 when not energized. The atmosphere release pipe 17 is connected to the oil separator 11 side of the check valve 14R of the blow-by gas pipe 15R. The atmosphere release pipe 17 may also be connected to the oil separator 11 side of the check valve 14L of the blow-by gas pipe 15L and to the intake pipe 4L on the upstream side of the compressor 5L. Furthermore, since one end of the atmosphere release pipe 17 only needs to be open to the atmosphere, it does not have to be connected to either the intake pipe 4L or 4R.

[0019] During natural aspiration, the pressure in the oil tank 10 and oil separator 11 becomes higher than the pressure in the surge tanks 7L and 7R. This opens the check valves 14L and 14R, and the blow-by gas in the oil separator 11 is supplied to combustion in the engine 1 via blow-by gas pipes 15L and 15R. During supercharging, the pressure in the oil tank 10 and oil separator 11 becomes higher than the pressure upstream of the compressors 5L and 5R. This opens the check valves 12L and 12R, and the blow-by gas in the oil separator 11 is supplied to combustion in the engine 1 via blow-by gas pipes 13L and 13R.

[0020] In this way, the scavenging pump P, the oil pipe 10a, and the oil tank 10 recover oil used in the engine 1. In addition, the scavenging pump P, the oil pipe 10a, the oil tank 10, the oil separator 11, and the blow-by gas pipes 13L, 13R, 15L, and 15R return blow-by gas generated within the engine 1 to the engine 1. Therefore, these mechanisms are mechanisms for achieving the recovery of oil and the return of blow-by gas.

[0021] When a request to stop the engine 1 is made, the throttle valves 6L and 6R are relatively small, and the pressure in the surge tanks 7L and 7R is negative. This also creates a negative pressure in the oil tank 10, which is connected to the surge tanks 7L and 7R via the blow-by gas pipes 15L and 15R. The engine 1 may stop in this state. In this case, the pressure in the surge tanks 7L and 7R returns to atmospheric pressure. However, the check valves 12L, 12R, 14L, and 14R may maintain a negative pressure in the oil tank 10. To eliminate this negative pressure, if the pressure in the oil tank 10 is negative when the engine 1 is stopped, the ECU 20 opens the air release valve 18 to open the oil tank 10 to the atmosphere. This release may allow a large amount of air to flow into the oil tank 10, potentially generating airflow noise. In this embodiment, a diagnostician can use the diagnostic terminal 40 to diagnose whether the abnormal noise occurring in the vehicle A is caused by the oil tank 10 being opened to the atmosphere when the engine 1 is stopped.

[0022] [Abnormal noise diagnosis control] 3 is a flowchart showing an example of abnormal sound diagnosis control. It is assumed that this control is executed by a diagnostician operating the diagnostic terminal 40 near or inside vehicle A when the vehicle A is stopped with the engine 1 running. This control is also executed by the CPU 42 in accordance with the abnormal sound diagnosis program 44a.

[0023] First, the CPU 42 reads information about the vehicle A via the dongle 21 (step S1). The information about the vehicle A includes, for example, the vehicle model, the engine model, the serial number, the presence or absence of a dry sump oil tank, the engine speed, the intake air amount, the fuel injection state, the oil / water temperature, the intake air temperature, the state of the variable valve system, the gear position of the transmission, the remaining charge of the hybrid battery, the pressure values ​​and temperature values ​​of various sensors, etc.

[0024] Next, the CPU 42 starts recording the abnormal noise of the vehicle A via the microphone 52 (step S2). Next, the CPU 42 determines whether or not the vehicle A is equipped with a dry sump oil tank based on the vehicle information (step S3). Note that step S3 is not limited to being determined by the CPU 42 based on the vehicle information. For example, the CPU 42 may display a selection screen on the display 46 for the presence or absence of a dry sump oil tank, and the diagnostician may manually select whether or not the tank is equipped with a dry sump oil tank. The case where the answer to step S3 is No will be described later.

[0025] If the answer is Yes in step S3, the CPU 42 determines whether the diagnosis target is an abnormal noise made when the engine 1 is stopped (step S4). Specifically, the CPU 42 displays a selection screen on the display 46 for selecting whether the diagnosis target is an abnormal noise made when the engine 1 is stopped, and the diagnostician manually makes the selection. The case where the answer is No in step S4 will be described later.

[0026] If the answer to step S4 is Yes, the CPU 42 sends an instruction to the ECU 20 to stop the engine 1 while maintaining negative pressure in the oil tank 10 (step S5). For example, when the engine 1 is idling, the throttle valves 6L and 6R are set to a relatively small opening, which causes negative pressure in the surge tanks 7L and 7R. Accordingly, the pressure in the oil tank 10, which is connected to the surge tanks 7L and 7R via the blow-by gas pipes 15L and 15R, also becomes negative. By stopping the engine 1 while the pressure in the oil tank 10 is negative, the air release valve 18 is thought to open when the engine 1 is stopped. In step S5, the CPU 42 may display the above instruction on the display 46 for the diagnostician. By executing step S5, the engine 1 is stopped after a predetermined time has elapsed.

[0027] Next, the CPU 42 transmits a command to the ECU 20 to prohibit the atmosphere release valve 18 from opening before the engine 1 is stopped (step S6). Note that instead of step S6, the CPU 42 may display on the display 46 an instruction for the diagnostician to manually unplug the connector of the atmosphere release valve 18 before the engine 1 is stopped.

[0028] Next, the CPU 42 determines whether or not the abnormal noise generated when the engine 1 is stopped has been eliminated based on the abnormal noise recording result (step S7). Step S7 is an example of a determination process. The case where the result in step S7 is No will be described later.

[0029] If the answer is Yes in step S7, the CPU 42 sends an instruction to the ECU 20 to open the atmosphere release valve 18 (step S8). This eliminates the negative pressure in the oil tank 10. Next, the CPU 42 diagnoses that the cause of the abnormal noise is the atmosphere release valve 18 being open when the engine 1 is stopped (step S9). Step S9 is an example of diagnostic processing.

[0030] If the answer is No in any of steps S3, S4, and S7, the CPU 42 uses a discrimination model that has been machine-learned through supervised learning to extract candidate causes of the abnormal noise (step S10). By inputting the abnormal noise into the discrimination model, the discrimination model outputs candidate causes of the abnormal noise. Candidate causes of the abnormal noise include, for example, valve opening / closing control performed after engine 1 is stopped, initialization control for adjusting the zero point of the valve position, differences in thermal expansion of exhaust pipe gaskets after engine 1 is stopped, flow of air conditioner or coolant, and blow-by due to damaged piping.

[0031] After executing step S9 or S10, the CPU 42 displays the diagnosis result on the display 46 (step S11). When step S9 is executed, the display 46 displays that the cause of the abnormal noise is the oil tank 10 being open to the atmosphere. When step S10 is executed, the display 46 displays candidate causes of the abnormal noise extracted by the determination model.

[0032] As described above, by using the diagnostic terminal 40 having the abnormal sound diagnosis program 44a installed, it is possible to accurately diagnose that the cause of the abnormal sound of the vehicle A is the open atmosphere release valve 18 when the engine 1 is stopped. This allows the diagnostician, even if he or she has no knowledge of abnormal sounds, to easily identify the cause of the abnormal sound. Furthermore, by installing the abnormal sound diagnosis program 44a in the diagnostic terminal 40, such a diagnosis can be achieved at low cost.

[0033] Although the embodiments of the present invention have been described in detail above, the present invention is not limited to such specific embodiments, and various modifications and variations are possible within the scope of the gist of the present invention as defined in the claims. [Explanation of symbols]

[0034] Vehicle A B. Engine System 1 engine 4L, 4R intake pipe 10 Oil Tank 10a Oil piping 12L, 12R, 14L, and 14R check valves 13L, 13R, 15L, 15R Blow-by gas piping 18 Atmospheric release valve 20 ECU (control unit) 40 Diagnostic terminal (computer) 44a Abnormal noise diagnosis program

Claims

[Claim 1] The engine and an oil tank that stores oil for lubricating the engine; an oil pipe through which the oil flows from the oil tank to the engine and through which blow-by gas flows from the engine to the oil tank; a blow-by gas pipe for allowing the blow-by gas to flow from the oil tank to an intake pipe of the engine; a check valve that is provided in the blow-by gas piping and allows the blow-by gas to flow from the oil tank to the intake pipe but restricts the flow of the blow-by gas in the reverse direction; an atmosphere release valve that opens the oil tank to the atmosphere when the pressure in the oil tank becomes negative when the engine is stopped; An abnormal noise diagnosis program for diagnosing an abnormal noise of a vehicle, comprising: a determination process for determining whether or not an abnormal noise that occurred when the engine was stopped due to a negative pressure in the oil tank was eliminated by the atmosphere release valve not opening; a diagnostic process for diagnosing that the cause of the abnormal noise is the opening of the atmosphere release valve when the engine is stopped, if a positive determination is made by the determination process; An abnormal noise diagnosis program that allows a computer to execute the above.

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